The present invention relates generally to devices that can disrupt or disarm the circuit or components of a terrorist-type bomb, using a fluid-filled bottle with an internal explosive charge that propels the fluid at the target to disable it.
In the art of bomb-disablement, most terrorist-type bombs are generally defused remotely by a propellant-actuated, gun-type disrupter expelling water. These disrupters (generally 12-ga.) are limited in their performance to small (lunchbox or briefcase size) packages or containers. Water-bottle disrupters can deliver large quantities of energy and are capable of destroying very large targets with controlled impact pressures. These water-bottle disrupters produce low-density spatial water jets that produce high levels of energy but have limited penetration capabilities.
In the past, most terrorist-type bombs or improvised explosive devices (IEDs) were remotely defused or disrupted with a gun-type disrupter. The disrupter consisted of a metal tube or barrel containing a propellant load in the breech end and, in the remaining portion of the barrel, containing a liquid projectile such as water. In U.S. Pat. No. 4,169,403, several grams of black powder, electrically initiated, propels the liquid out of the barrel to accomplish destruction of an IED. U.S. Pat. No. 4,957,027 discloses a versatile non-electric de-armer/disrupter that is propellant-actuated that propels various projectiles or missiles at an IED to disable or destroy it. This patent further teaches the ability to fire a plurality of disrupters/de-armers with various projectiles with a high degree of simultaneity. Variations of the disrupter illustrated in U.S. Pat. No. 4,957,027 have been developed to fire oil-based and metal-loaded clay from a similar device to remotely disable an IED.
Water systems using a high explosive to propel the water are illustrated in U.S. Pat. No. 4,955,939. This patent employs a high explosive to generate a shock wave through a liquid to provide sufficient pressure to collapse a plastic liner to form a plastic precursor jet capable of penetrating and creating a small hole through thick steel barriers. It goes on to state that the plastic precursor jet first penetrates the target, creating a small hole to allow the water from the charge to follow through the small entry hole. The efficiency of this system depends on the size of the precursor hole produced. If the barrier is strong, i.e., thick steel, then a small precursor hole will be formed. If too small, then only a fraction of the water will follow through the precursor hole. Other types of water charges that are explosively driven have been used in Explosive Ordnance Disposal (EOD) in the past. One such device used high explosives to accelerate water contained in a plastic bowl to dynamically disable an IED. The shock pressure accelerated the water from the detonating explosive. The hemispherical shape of the explosive enveloping the water directed the water into a jet capable of penetrating multiple barriers. Other techniques involved the use of explosives to propel water to create a low-density, high-energy water jet capable of penetrating soft skinned IEDs containing sensitive nitroglycerin-based dynamites without initiation. These devices employed a central tubular charge in a fluidfilled container, such as a 55-gal. drum, which was then fired adjacent the target.
The prior art devices, therefore, had shortcomings. The disrupter-fired fluids, as well as the bowl surrounded by charges, impacted a target over a relatively small surface area, creating a very high pressure. The prior design involving containers with fluid fill and a centrally mounted explosive created a low-density spatial water jet that impacted a tremendous amount of the surface area. Thus, one of the objectives of the present invention is to combine the beneficial qualities of both of the previous types of devices used to disable IEDs. One of the objectives of the present invention is to be able to vary variables such as the velocity of the fluid jet, its density, its impact pressure, and the standoff or distance capability from the IED. This allows EOD personnel to adapt to the situation by configuring the apparatus to either extreme or points in between.
Accordingly, the present invention teaches a unique explosive-disabling charge that explosively propels a variety of materials at the IED in a variable manner to suit a particular situation. The inventor refers to the present invention by the name "Hydra-Jet". The present invention combines the beneficial features of gun-barrel-shaped disruptive tools as well as the water-bottle-shaped disrupter tools in a single device and builds the device from readily available materials. The present invention includes a device with a fixed charge in a particular direction with means for varying, either locally or remotely to the size and velocity of the projectile. An advantage of the present invention is the ability to vary the projectile's shape without altering the container or varying the amount of explosive. While the present invention uses a predetermined explosive charge, it has the ability to vary the projectile mass, velocity, energy and shock pressure delivered to the target. Another advantage of the present invention is to mass-focus the water or other propellant so as to forms a stable fluid projectile that is capable of delivering its energy to the target at long standoff distances in excess of 5 feet. Yet another advantage of the present invention is to present a shaped, confined charge which operates very efficiently to produce a high-energy disabling jet with a minimal amount of explosives, thus reducing the possibility of collateral damage to the surrounding area. Another advantage of the present invention is the ability to have a choice in providing a large-surface-impact-area jet for general disruption purposes or a focused or concentrated jet for more precise disruption. Another advantage is to allow variability in the projectile velocity by a factor of 4 without altering the explosive quantity in the container, while retaining the capability of providing velocities that can range from a few hundred ft/sec to several thousand ft/sec.
Another advantage of the present invention is the ability to increase the impact pressure from the projectile of the apparatus by a factor of 16, thus allowing penetration of strong barriers such as 1/8" thick steel or more without initiating the IED inside. The apparatus can be used alone or in combination with other devices that can be sequentially timed with microsecond resolution. The invention can also provide the ability to create viewing ports in conjunction with long standoff distances in the sides of trucks or other vehicles at short or large standoff distances with minimal effect to nearby property or personnel. Another advantage of the present invention is for use in the motion picture business to create special effects of fireballs by using a flammable material that is propelled explosively. The invention has the further advantage of being able to penetrate a multiplicity of layers of barrier materials and still have enough energy to disable or destroy the circuit and other components of the IED from distances as far as 5-6 feet away or more or at closer offsets. These advantages can be readily understood by those skilled in the art from a review of a detailed description of the invention below.